# Python program to get maximum of each key Dictionary List

• Last Updated : 11 Dec, 2020

Given list of dictionaries, write a Python program to get maximum of each key.

Examples:

Input : test_list = [{“Gfg” : 8, “is” : 1, “Best” : 9}, {“Gfg” : 2, “is” : 9, “Best” : 1}, {“Gfg” : 5, “is” : 10, “Best” : 7}]
Output : {‘Gfg’: 8, ‘is’: 10, ‘Best’: 9}
Explanation : Maximum of Gfg key is 8 among possible 8, 2 and 5.

Input : test_list = [{“Gfg” : 8, “is” : 1, “Best” : 9}, {“Gfg” : 5, “is” : 10, “Best” : 7}]
Output : {‘Gfg’: 8, ‘is’: 10, ‘Best’: 9}
Explanation : Maximum of Best key is 7 among possible 9, 7.

Method #1 : Using items() + loop + max()

In this, we iterate for each dictionary and keys in them using loop and keep updating maximum values for each key using max().

## Python3

 `# Python3 code to demonstrate working of``# All Keys Maximum in Dictionary List``# Using items() + loop + max()`` ` `# initializing Matrix``test_list ``=` `[{``"Gfg"``: ``8``, ``"is"``: ``1``, ``"Best"``: ``9``},``             ``{``"Gfg"``: ``2``, ``"is"``: ``9``, ``"Best"``: ``1``},``             ``{``"Gfg"``: ``5``, ``"is"``: ``10``, ``"Best"``: ``7``}]`` ` `# printing original list``print``(``"The original list is : "` `+` `str``(test_list))`` ` ` ` `res ``=` `{}``for` `dic ``in` `test_list:``    ``for` `key, val ``in` `dic.items():`` ` `        ``# checking for key presence and updating max``        ``if` `key ``in` `res:``            ``res[key] ``=` `max``(res[key], val)``        ``else``:``            ``res[key] ``=` `val`` ` `# printing result``print``(``"All keys maximum : "` `+` `str``(res))`

Output:

The original list is : [{‘Gfg’: 8, ‘is’: 1, ‘Best’: 9}, {‘Gfg’: 2, ‘is’: 9, ‘Best’: 1},
{‘Gfg’: 5, ‘is’: 10, ‘Best’: 7}]
All keys maximum : {‘Gfg’: 8, ‘is’: 10, ‘Best’: 9}The original list is : [{‘Gfg’: 8, ‘is’: 1, ‘Best’: 9},
{‘Gfg’: 2, ‘is’: 9, ‘Best’: 1}, {‘Gfg’: 5, ‘is’: 10, ‘Best’: 7}]
All keys maximum : {‘Gfg’: 8, ‘is’: 10, ‘Best’: 9}

Method #2 : Using defaultdict()

In this, we omit step of conditional check for key existence by using defaultdict(). Rest all the functionalities are similar to above method.

## Python3

 `# Python3 code to demonstrate working of``# All Keys Maximum in Dictionary List``# Using defaultdict()``from` `collections ``import` `defaultdict`` ` `# initializing Matrix``test_list ``=` `[{``"Gfg"``: ``8``, ``"is"``: ``1``, ``"Best"``: ``9``},``             ``{``"Gfg"``: ``2``, ``"is"``: ``9``, ``"Best"``: ``1``},``             ``{``"Gfg"``: ``5``, ``"is"``: ``10``, ``"Best"``: ``7``}]`` ` `# printing original list``print``(``"The original list is : "` `+` `str``(test_list))`` ` ` ` `res ``=` `defaultdict(``int``)``for` `dic ``in` `test_list:``    ``for` `key, val ``in` `dic.items():`` ` `        ``# defaultdict helps to avoid conditional check here``        ``res[key] ``=` `max``(res[key], val)`` ` `# printing result``print``(``"All keys maximum : "` `+` `str``(``dict``(res)))`

Output:

The original list is : [{‘Gfg’: 8, ‘is’: 1, ‘Best’: 9}, {‘Gfg’: 2, ‘is’: 9, ‘Best’: 1},
{‘Gfg’: 5, ‘is’: 10, ‘Best’: 7}]
All keys maximum : {‘Gfg’: 8, ‘is’: 10, ‘Best’: 9}

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